看板 Math 關於我們 聯絡資訊
※ 引述《maggie531 (一起走吧~)》之銘言: : 請教各位大神,這三題該如何解 : 感謝各位幫忙 : : https://i.imgur.com/Oj4WhDL.jpg
1. m正整數 > (a - 1) a^2 - a + 3 = (a - 1)m => (a - 1)(m - a) = 3 a - 1 = 1(不合) a - 1 = 3 => a = 4, m = a + 1 = 5 2. N - [N] = [N] - (N - [N]) = 2[N] - N => 2N = 3[N] 0 <= 2[N] - N = N - [N] < 1 => 0 <= [N] < 2 [N] = 0 = N(不合) [N] = 1 => N = 3/2 3. 開頭為n的會結束於n + n + 3 - 1 = 2n + 2 2n + 2 = 2018 => n = 1008 開頭為1008 ~ 2018的人都會叫到2018 共n + 3 = 1011人 -- ※ 發信站: 批踢踢實業坊(ptt.cc), 來自: 39.13.34.1 (臺灣) ※ 文章網址: https://www.ptt.cc/bbs/Math/M.1578491351.A.B7E.html
JI1 : trinity: father, son, holy ghost 01/09 09:01
maggie531 : 謝謝h大幫忙:) 01/11 11:40